1. Field of Invention
The embodiment of the present invention relates generally to basic electronic circuitry and, more particularly, to an operational amplifying device.
2. Description of Related Art
In the Gamma correction design, it is common to use an op-amp (operational amplifier) as a voltage follower connecting to different resistor arrays for different Gamma curve applications. Conventionally, a switch is placed following the op-amp output to switch to the different resistor arrays.
However, the switches placed outside the op-amp introduce a voltage drop (IR drop), and this voltage drop degrades the precision of the Gamma correction. In order to reduce the voltage drop, it is required to use large switches, but this results in a large area of occupation.
In order to solve the above problems, those skilled in the art are striving to find a solution, but no applicable method has yet been put forward. Therefore, there is a need to improve the voltage drop introduced by switches placed outside an op-amp and further improve the problem of large area occupation resulting from the use of large switches in an effort to reduce the voltage drop.